Portable electronic devices have been increasingly used in fields of industry and lifestyle due to supporting particular user functions and having a size small enough to carry. Recently, new portable electronic devices have been developed which integrally support diverse user functions. The portable electronic devices support user functions and provide a screen corresponding to a corresponding user function through the display unit. Accordingly, the user views the screen output on the display unit when using the specific user function and uses the corresponding function.
Portable electronic devices of the related art support a function of writing text, drawing pictures, and the like by using an electronic pen operated by electromagnetic induction. The electronic pen detects a specific input signal from the portable electronic device while contacting with the display unit. Accordingly, the user may perform a function of writing and the like on the display unit of the portable electronic device by operating the electronic pen. Since angles formed by the user's grasp of the electronic pen may be different from each other, errors between a point where an actual electronic pen is contacted with the display unit and a point where the electronic pen which is recognized by the portable electronic device are generated. To correct the errors, the related art employs a table with previously defined eight coordinate correction values of an electronic pen, in which there are two forms including a left-handed standard angle (hereinafter, referred to as “a grip angle of the left-hand”) and a right-handed standard angle (hereinafter, referred to as “a grip angle of the right-hand”) according to a form of the pen grip of the user, and four forms including a form of forward/reverse or a transverse/longitudinal direction according to the arrangement state of the portable electronic device on the basis of the front side of the user who grasps the portable electronic device. A coordinate of the electromagnetic induction point formed by the electronic pen is corrected as a coordinate of the point that is formed by the contact of the electronic pen with the display unit by using a table storing the previously defined grip angle and the previously defined error correction distance (hereinafter, referred to as “a standard inclination correction distance”). The grip angle of the left-hand, the grip angle of the right-hand, and the standard inclination correction distance are numeric values defined previously by statistics or experiments.
However, this method of solving problems arising in the related art could be properly applied only to a case where the portable electronic device was inclined to the ground by greater than or equal to a predetermined angle and it was not possible to correct the coordinate of the electronic pen accurately because the arrangement state of the portable electronic device could not be recognized smoothly when the portable electronic device was laid horizontal to the ground. As a result, inconveniences are produced because the arrangement state of the portable electronic device cannot be confirmed as it is necessary to identify the arrangement state of the portable electronic device by inclining the portable electronic device laid in a horizontal state by a predetermined angle and then converting the portable electronic device into the horizontal state again.
In addition, when the user inputs signals by the electronic pen while the arrangement state of the portable electronic device is not accurately recognized, errors may increase because of the use of the pre-defined correction angle and correction distance values, which are not consistent with the arrangement state of the portable electronic device.
Furthermore, the related art has a limitation in that various errors, generated according to the changed rotation state of the portable electronic device by providing only whole eight coordinate correction values, cannot be reflected and the identical standard inclination distance is applied even though the inclination angle of the electronic pen is changed when the user writes text.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.